Scientists create artificial gut for lab tests

A three-dimensional tissue model of the human gut has been developed that will aid in the study of gastrointestinal diseases.

Until now, scientists have had to rely on two-dimensional cultures or live animal models, but the novel 3D hydrogel scaffold method will offer more realistic physiological conditions.

The researchers are particularly interested how gut bacteria can be used to induce intestinal cells to behave like insulin-producing beta cells — a project that could result in a simple oral treatment of type 1 diabetes.

’We knew the flat models weren’t accurate. Cells behave differently in different 3D environments …this will enable us to better study drug absorptions and interactions between epithelia and bacteria in the intestine,’ said project lead Prof John March of the Department of Biological and Environmental Engineering at Cornell University in the US.

The team created a hard plastic mould, then covered it with a softer, so-called sacrificial mould, made from calcium alginate that could be dissolved, leaving a collagen scaffold upon which live cells could be grown.

The researchers tested the model by seeding it with human colon cells. After being cultured for three weeks, it was covered with fingerlike structures mimicking the intestinal villi, the threadlike projections covering the surface of the mucous membrane in the small intestine where fluids and nutrients are absorbed.

In this way, they avoided damaging the delicate shapes during separation of the moulds.

Scientists had previously managed to fabricate models as small as 1 or 2 microns, but slightly larger sizes have eluded them.

The artificial gut March and team created is around 1mm high and 200 microns across, and is easily visible under a scanning electron microscope. They are in the process of acquiring patents for the technology, which could be used in other areas of biomedical research, such as tissue engineering, pharmaceutical sciences and cell biology.

Confocal microscope image of caco-2 cells on collagen scaffold, after staining for actin (green) and nucleic acid (blue)
Confocal microscope image of caco-2 cells on collagen scaffold, after staining for actin (green) and nucleic acid (blue)